Functionalized Polymers from -Hydroxyalkylated N-Vinylcaprolactam

Hydroxyalkylation of N-vinylcaprolactam (NVCL) in -position via ring-opening reaction of propylene oxide and epsilon-caprolactone, respectively, yields in precursors for multifunctional NVCL derivatives. Homo- and copolymers of hydroxyfunctionalized NVCL derivatives, synthesized by free radical mechanism, are further investigated regarding their thermoresponsive behavior. Esterification of hydroxypropylated NVCL derivative with methacrylic anhydride is carried out yielding a versatile bifunctional cross-linker. Networks are obtained either via free radical polymerization of the cross-linker or anionic polymerization of only the methacrylic function and subsequent polymer analogous cross-linking of the vinylic side groups. The rheological behavior during and after curing is investigated by oscillatory rheology. Furthermore, N-vinylcaprolactam anion is used as an initiator for the anionic ring-opening polymerization of epsilon-caprolactone. Copolymerization of poly(epsilon-caprolactone) macromonomer with NVCL yields graft copolymers. A polymerizable thermotropic liquid crystalline (LC) derivative is prepared by coupling cholesteryl chloroformate to NVCL. The thermal behavior of LC derivative is investigated by differential scanning calorimetry and polarized light microscopy.